<?php
/*
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.doctrine-project.org>.
 */

namespace Doctrine\DBAL;

use Doctrine\Common\EventManager;

/**
 * Factory for creating Doctrine\DBAL\Connection instances.
 *
 * @author Roman Borschel <roman@code-factory.org>
 * @since 2.0
 */
final class DriverManager {
	/**
	 * List of supported drivers and their mappings to the driver classes.
	 *
	 * @var array
	 * @todo REMOVE. Users should directly supply class names instead.
	 */
	private static $_driverMap = array( 'pdo_mysql' => 'Doctrine\DBAL\Driver\PDOMySql\Driver', 'pdo_sqlite' => 'Doctrine\DBAL\Driver\PDOSqlite\Driver', 'pdo_pgsql' => 'Doctrine\DBAL\Driver\PDOPgSql\Driver', 'pdo_oci' => 'Doctrine\DBAL\Driver\PDOOracle\Driver', 'oci8' => 'Doctrine\DBAL\Driver\OCI8\Driver', 'ibm_db2' => 'Doctrine\DBAL\Driver\IBMDB2\DB2Driver', 'pdo_ibm' => 'Doctrine\DBAL\Driver\PDOIbm\Driver', 'pdo_sqlsrv' => 'Doctrine\DBAL\Driver\PDOSqlsrv\Driver' );
	
	/** Private constructor. This class cannot be instantiated. */
	private function __construct() {}
	
	/**
	 * Creates a connection object based on the specified parameters.
	 * This method returns a Doctrine\DBAL\Connection which wraps the underlying
	 * driver connection.
	 *
	 * $params must contain at least one of the following.
	 * 
	 * Either 'driver' with one of the following values:
	 * pdo_mysql
	 * pdo_sqlite
	 * pdo_pgsql
	 * pdo_oracle
	 * pdo_sqlsrv
	 * 
	 * OR 'driverClass' that contains the full class name (with namespace) of the
	 * driver class to instantiate.
	 * 
	 * Other (optional) parameters:
	 * 
	 * <b>user (string)</b>:
	 * The username to use when connecting. 
	 * 
	 * <b>password (string)</b>:
	 * The password to use when connecting.
	 * 
	 * <b>driverOptions (array)</b>:
	 * Any additional driver-specific options for the driver. These are just passed
	 * through to the driver.
	 * 
	 * <b>pdo</b>:
	 * You can pass an existing PDO instance through this parameter. The PDO
	 * instance will be wrapped in a Doctrine\DBAL\Connection.
	 * 
	 * <b>wrapperClass</b>:
	 * You may specify a custom wrapper class through the 'wrapperClass'
	 * parameter but this class MUST inherit from Doctrine\DBAL\Connection.
	 * 
	 * @param array $params The parameters.
	 * @param Doctrine\DBAL\Configuration The configuration to use.
	 * @param Doctrine\Common\EventManager The event manager to use.
	 * @return Doctrine\DBAL\Connection
	 */
	public static function getConnection(array $params, Configuration $config = null, EventManager $eventManager = null) {
		// create default config and event manager, if not set
		if( !$config ) {
			$config = new Configuration();
		}
		if( !$eventManager ) {
			$eventManager = new EventManager();
		}
		
		// check for existing pdo object
		if( isset( $params['pdo'] ) && !$params['pdo'] instanceof \PDO ) {
			throw DBALException::invalidPdoInstance();
		} else if( isset( $params['pdo'] ) ) {
			$params['pdo']->setAttribute( \PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION );
			$params['driver'] = 'pdo_' . $params['pdo']->getAttribute( \PDO::ATTR_DRIVER_NAME );
		} else {
			self::_checkParams( $params );
		}
		if( isset( $params['driverClass'] ) ) {
			$className = $params['driverClass'];
		} else {
			$className = self::$_driverMap[$params['driver']];
		}
		
		$driver = new $className();
		
		$wrapperClass = 'Doctrine\DBAL\Connection';
		if( isset( $params['wrapperClass'] ) ) {
			if( is_subclass_of( $params['wrapperClass'], $wrapperClass ) ) {
				$wrapperClass = $params['wrapperClass'];
			} else {
				throw DBALException::invalidWrapperClass( $params['wrapperClass'] );
			}
		}
		
		return new $wrapperClass( $params, $driver, $config, $eventManager );
	}
	
	/**
	 * Checks the list of parameters.
	 *
	 * @param array $params
	 */
	private static function _checkParams(array $params) {
		// check existance of mandatory parameters
		

		// driver
		if( !isset( $params['driver'] ) && !isset( $params['driverClass'] ) ) {
			throw DBALException::driverRequired();
		}
		
		// check validity of parameters
		

		// driver
		if( isset( $params['driver'] ) && !isset( self::$_driverMap[$params['driver']] ) ) {
			throw DBALException::unknownDriver( $params['driver'], array_keys( self::$_driverMap ) );
		}
		
		if( isset( $params['driverClass'] ) && !in_array( 'Doctrine\DBAL\Driver', class_implements( $params['driverClass'], true ) ) ) {
			throw DBALException::invalidDriverClass( $params['driverClass'] );
		}
	}
}